The Effect of Injection-Production Process Parameters on the Fatigue Life of High-Pressure Injection-Production String

During the operation of underground gas storage, the periodic internal pressure fluctuations in high-pressure injection-production stringInjection-production string have a significant impact on the fatigue lifeFatigue life of the string. This study established a localized fatigue simulation model for the injection-production stringInjection-production string and investigated the effects of factors such as average internal pressure, alternating load amplitude and frequency, and wall thickness reduction on fatigue lifeFatigue life. The results indicate that as the average internal pressure, alternating load amplitude and frequency, and wall thickness reduction increase, the fatigue lifeFatigue life of the string diminishes. Among these factors, the average internal pressure has the greatest influence on the fatigue lifeFatigue life. When the average internal pressure increases from 20 to 45 MPa, the fatigue lifeFatigue life decreases from 6.999 × 1013 cycles to 4.984 × 105 cycles. The research findings provide a theoretical basis for optimizing the injection-production processProcess of underground gas storage and preventing fatigue failure in the string.